Contributions to the Methodology of Electrocardiographic Imaging (ECGI) and Application of ECGI to Study Mechanisms of Atrial Arrhythmia, Post Myocardial Infarction Electrophysiological Substrate, and Ventricular Tachycardia in Patients

The spatial accuracy in determining initiation sites as simulated by atrial pacing was ä 6mm. ECGI imaged many activation patterns of commonly multiple wavelets (92%), with pulmonary vein (69%) and non-pulmonary vein (62%) trigger sites. Rotor activity was seen rarely (15%). AF complexity increased with longer clinical history of AF, though the degree of complexity of nonparoxysmal AF varied and overlapped. ECGI offers a way to identify unique epicardial activation patterns of AF in a patient-specific manner. The results are consistent with contemporary animal models of AF mechanisms and highlight the coexistence of a variety of mechanisms among patients.